AwaitMultiple 4.0.1

AwaitMultiple

Await multiple tasks in parallel and get their return values with concise code.

How to use and why

AwaitMultiple can be used like this up to 16 arguments:

var (value1, value2, value3) = await Tasks(task1, task2, task3);

Add:

global using static AwaitMultiple.Await;

Write

var (books, employees) = await Tasks(
   dbConnection.GetAllAsync<Books>(),
   dbConnection.GetAllAsync<Employees>());

instead of

var books = await dbConnection.GetAllAsync<Book>();
var employees = await dbConnection.GetAllAsync<Employee>();

because the latter code is not executing the employees-related task until the books-related task has finished.

Optional feature

Await tasks with and without return value together:

var (books, employees) = await Tasks(
   dbConnection.GetAllAsync<Books>(),
   dbConnection.GetAllAsync<Employees>(),
   [
      dbConnection.InsertHistoryRecordAsync(),
      // ... any number of tasks...
   ]);

or

var books = await Tasks(
   dbConnection.GetAllAsync<Books>(),
   [
      dbConnection.InsertHistoryRecordAsync(),
      // ... any number of tasks...
   ]);

or even (for code consistency):

await Tasks([
   dbConnection.InsertHistoryRecordAsync(),
   // ... any number of tasks...
]);

Exception handling options

By default, only the first occurring exception is thrown (and the others are caught but not re-thrown). This is consistent with Task.WhenAll and more parts of the C# language.

You can change this behavior by setting the exceptionOption like this:

var (books, employees) = await Tasks(
   dbConnection.GetAllAsync<Books>(),
   dbConnection.GetAllAsync<Employees>(),
   exceptionOption: ExceptionOption.Aggregate);

Then all errors are returned in a single AggregateException. Its Message property is like:

One or more errors occurred. (First exception message.) (Second exception message.)

Use the property aggregateException.InnerExceptions for more details like StackTraces etc.

Configuring the await

Optionally, you can configure the await:

var (books, employees) = await Tasks(
   dbConnection.GetAllAsync<Books>(),
   dbConnection.GetAllAsync<Employees>(),
   continueOnCapturedContext: false)
   .ConfigureAwait(false);

Get it

Available via NuGet.